
TY  - JOUR
A1  - Brown, RFC 
A1  - Eastwood, FW 
A1  - Harrington, KJ 
A1  - McMullen, GL 
T1  - Methyleneketenes and methylenecarbenes. III. Pyrolytic synthesis of arylacetylenes and their thermal rearrangements involving arylrnethylenecarbenes
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1974
VL  - 27
IS  - 11
SP  - 2391
EP  - 2402
KW  - 
UR  - https://doi.org/10.1071/CH9742393 
N2  - Flash vacuum pyrolysis (550-600°) of 5-benzylidene derivatives of 2,2- dimethyl-1,3-dioxan-4,6-dione(isopropylidene malonate) gives phenylacetylenes bearing m- or p-substituents (H, Me, MeO, Cl, CN)in 64-98% yield. o-Methoxy- and o-phenyl-benzylidene derivatives give the arylacetylenes even at 420°. Arylacetylenes equilibrate with arylmethylenecarbenes, ArCH=C:, at 550-720°, as shown by labelling experiments using 13C and by the formation of products of interaction with o-substituents. Methylenebenzocyclobutene and o-tolylacetylene each form indene at 700-720°. 
ER  -

